For any public health intervention, a high‐quality impact analysis is critical to shaping and prioritizing policies, and ensuring that the intervention will achieve its intended benefit. An impact analysis with ill informed or inflated assumptions may over‐promise results that are unrealistic. This runs the risk of masking further improvements that may be needed to achieve the desired impact, and can even divert focus and resources away from other approaches.

When evaluating the benefits of the Medicine Patent Pool (MPP), it is therefore important to ensure that the methodology and assumptions underlying its impact analysis are sound. This means ensuring that its analyses are based on realistic (and not overly optimistic) scenarios; use appropriate historical data to inform key assumptions; and compare results to the counter factual (i.e. status quo) scenario to determine direct incremental benefits.

Using these principles, we have prepared the following analysis as a response to claims made by the MPP about its economic benefits, as elaborated in "Annex 10: Economic Benefits of the Pool" presented to the UNITAID Executive Board in Dec‐2009. The categories of savings in Section A of this analysis are consistent with those in the original MPP document to allow for a side‐by‐side comparison. For each category, we have provided an explanation of our methodology and how it differs from that of the MPP. While all calculations in Section A are based on a hypothetical MPP deal, Section B of this document discusses the financial impact of the actual deal that MPP has recently negotiated with Gilead...